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Updated: Jul 11, 2026

Electromyometrial Imaging of Uterine Contractions in Pregnant Women
Published on: May 26, 2023
When it comes to pregnant women sleeping, is left right?
1Department of Obstetrics and Gynaecology, Mount Sinai Hospital, University of Toronto, Toronto ON.
Abstract:
Pregnant women who lie in a supine position may develop syncopal symptoms. However, of those women who become symptomatic, only 2% to 4% have significant aortocaval compression. Even in this small minority of symptomatic women, there is no evidence of fetal compromise. The advice often given to pregnant women to lie on the left side is therefore not relevant. In some women, experiencing a pre-syncopal episode will cause them to avoid lying in the supine position.
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